Speed problem - smbclient doesn't send duplicate ACKs in case
of pacekt loss
Jeremy Allison
jra at samba.org
Thu Jan 6 00:15:22 GMT 2005
On Tue, Jan 04, 2005 at 12:46:17AM -0500, Derrell.Lipman at UnwiredUniverse.com wrote:
>
> - lib/util.c and lib/select.c
Your change to lib/util.c depends on nanosleep - a linux-only function. I'll
add this with a configure.in test.
> * In an application with signals, it was possible for functions to block
> indefinitely while awaiting timeouts. This patch ensures that if a system
> call with a timeout is aborted and needs to be restarted, it is restarted
> with a timeout which is adjusted for the amount of time already waited.
This is correct, but I think slightly less efficient than it could be, as it
does 2 gettimeofday calls per select. Can you give me an opinion on this
version, which I think does the same but with only one gettimeofday call ?
Thanks,
Jeremy.
Index: lib/select.c
===================================================================
--- lib/select.c (revision 4543)
+++ lib/select.c (working copy)
@@ -128,12 +128,24 @@
{
int ret;
fd_set *readfds2, readfds_buf, *writefds2, writefds_buf, *errorfds2, errorfds_buf;
- struct timeval tval2, *ptval;
+ struct timeval tval2, *ptval, end_time;
readfds2 = (readfds ? &readfds_buf : NULL);
writefds2 = (writefds ? &writefds_buf : NULL);
errorfds2 = (errorfds ? &errorfds_buf : NULL);
ptval = (tval ? &tval2 : NULL);
+ if (tval) {
+ GetTimeOfDay(&end_time);
+ end_time.tv_sec += tval->tv_sec;
+ end_time.tv_usec += tval->tv_usec;
+ end_time.tv_sec += end_time.tv_usec / 1000000;
+ end_time.tv_usec %= 1000000;
+ errno = 0;
+ tval2 = *tval;
+ ptval = &tval2;
+ } else {
+ ptval = NULL;
+ }
do {
if (readfds)
@@ -142,9 +154,20 @@
writefds_buf = *writefds;
if (errorfds)
errorfds_buf = *errorfds;
- if (tval)
- tval2 = *tval;
+ if (ptval && (errno == EINTR)) {
+ struct timeval now_time;
+ SMB_BIG_INT tdif;
+ GetTimeOfDay(&now_time);
+ tdif = usec_time_diff(&end_time, &now_time);
+ if (tdif <= 0) {
+ ret = 0; /* time expired. */
+ break;
+ }
+ ptval->tv_sec = tdif / 1000000;
+ ptval->tv_usec = tdif % 1000000;
+ }
+
ret = sys_select(maxfd, readfds2, writefds2, errorfds2, ptval);
} while (ret == -1 && errno == EINTR);
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